Ratings assign an A-F grade to each game reviewed, although it seems to me that the author loves almost every game. I was hardpressed to find a game in the book that scored below a C+. Some people might say "Ah, that shows that Jeff Rovin only reviews high-quality games!", but I also think that this shows that the game companies that paid the most money got better ratings.

I'm actually curious about this "Jeff Rovin". Between 1989 and 1992 he banged out six books in this series, and searching for him while preparing this writeup revealed that he's also written a number of crummy trivia books, joke books, and unauthorized biographies. Could "Jeff Rovin" be a pen name? A literary Alan Smithee? Is he a collection of writers, all working together under a single name? Notice above under "Rating" that the books says "We'll give you the lowdown". Some people have speculated that there really is a Jeff Rovin and that he wrote these books by having his friends' children buy, play through each game, take notes on the games, and then turn over all this research to Jeff who would compile it and publish it under his own name.

These books are an utter waste. However, in the interest of full disclosure, I bought HTWANG#1 and the Game Boy book in my youth. I was young; I didn't know what I was getting into! HTWANG#1 fell apart years ago and has long since been thrown away, although the Game Boy book survives thanks to it being stored in my rarely-opened Game Boy suitcase. If you should have a warped desire to read these books, your best bet in finding them is garage sales where they often go for a dime a piece. Personally, I think paying a dime is a little generous.

References:
I have the Game Boy book right here.
http://www.atarihq.com/tsr/books/rovin.html